Arrow with test

gistfile1.txt

// plugins {
//    id "org.jetbrains.kotlin.jvm" version "1.9.0"
//    implementation("io.arrow-kt:arrow-core:1.2.0")
//    implementation("io.arrow-kt:arrow-optics:1.2.0")
//    ksp("io.arrow-kt:arrow-optics-ksp-plugin:1.2.0")





package test

import io.sentry.protocol.User
import javax.management.Query

data class ConnectionParams(val host: String, val port: Int)
class Connection
class DatabaseConnection {
  suspend fun <A> execute(q: Query): Result<A> {
    return Result.success(null) as Result<A>
  }
}

interface Logger {
  suspend fun log(message: String): Unit
}

interface Database {
  suspend fun <A> execute(q: Query): Result<A>
}

suspend fun openDatabaseConnection(params: ConnectionParams): Connection {
  return Connection()
}

class DatabaseFromConnection(val conn: DatabaseConnection) : Database {
  override suspend fun <A> execute(q: Query): Result<A> =
    conn.execute(q)
}

interface Log {
  suspend fun log(message: String): Unit
}

suspend fun <Ctx> Ctx.saveUserInDb(user: String)
  where Ctx : Database, Ctx : Log {
  // prepare something
  val result = execute<String>(Query())
  if (result.isFailure) log("Big problem!")
  // keep doing stuff
}

suspend fun <A : Any> db(
  params: ConnectionParams,
  f: suspend Database.() -> A
): A {
  val conn = openDatabaseConnection(params) as DatabaseConnection
  return with(DatabaseFromConnection(conn), f)
}

class StdOutLogger() : Logger {
  override suspend fun log(message: String) {
    println(message)
  }
}

fun <A : Any> stdoutLogger(
  f: suspend Logger.() -> A
): A {
  return with(StdOutLogger(), f)
}

val connParams = ConnectionParams("localhost", 1234)

suspend fun example() {
  db(connParams) {
    stdoutLogger {
      with(object : Database by this@db, Logger as this@stdoutLogger) {
        saveUserInDb(User("Alex"))
      }
    }
  }
}